Heart valve and retaining means therefor

ABSTRACT

An arrangement for retaining a heart valve in a passageway of a cardiovascular system, and a heart valve useable therewith. The retaining arrangement includes an annular arrangement surrounding the circular heart valve and engaging it so as to be radially expandable and contractable relative thereto while securely holding the heart valve in place. The annular arrangement may include a single overlapping loop or a plurality of arcuate segments, all of which could slidingly engage a circumferentially extending flange on the outside of the heart valve. The heart valve includes a plurality of circular elements interfitting in a single plane to close the valve and extending axially relative to each other to open the valve and hence permit fluid flow through the passageway.

[451 Oct. 8, 1974" [54] HEART VALVE AND RETAINING MEANS THEREFOR [76]Inventor: Jordan D. Haller, 2701 W.

. Alameda, Burbank, Calif. 91505 [22] Filed: Nov. 17,1972 [21] Appl.No.: 307,351

[52] US. Cl 3/1, 3/DIG. 3,"l37/512.2,

[56] References Cited UNITED STATESPATENTS 3,378,029 4/1968 Lee3,579,642 5/1971 Heffernan et al 3/1 FOREIGN PATENTS OR APPLICATIONS482,441 12/1969 Switzerland 3/DlG. 3

OTHER PUBLICATIONS The In Vivo Comparison of Hemodynamic Function ofBall, Disk, and Eccentric Monocusp Artificial Mitral Valves, by R. W. M.Frater et al., Prosthetic Heart Valves, (Book), Charles C. Thomas,publisher,

1 1968, pages 262-277.

Primary Examiner-Richard A. Gaudet Assistant Examiner-Ronald L. FrinksAttorney, Agent, or Firm-Larson, Taylor and Hinds [5 7] ABSTRACT Anarrangement for retaining a heart valve in a passageway of acardiovascular system, and a heart valve useable therewith. Theretaining arrangement includes an annular arrangement surrounding thecircular heart valve and engaging it so as to be radially expandable andcont'ractable relative thereto while securely holding the heart valve inplace. The annular arrangement may include a single overlapping loop ora plurality of arcuate segments, all of which could slidingly engage acircumferentially extending flange on the outside of the heart valve.The heart valve includesa plurality of circular elements interfitting ina single plane to close the valve and extending axially relative to eachother to open the valve and hence permit fluid flow through thepassageway.

PATENTEB UB7 3 i 74 SREUIBF 3 Fla. 5

FIG. 4

HEART VALVE AND RETAINING MEANS THEREFOR BACKGROUND OF THE INVENTIONThis invention relates to a prosthetic device, and in particular itrelates to a valve structure useable as a heart valve; and thisinvention also relates to a retaining means for adjustably securing aheart valve in a passageway of a cardiovascular system.

'Many forms of heart valves are currently known and used. For example,one such device is shown in the Lee U.S. Pat. No. 3,378,029, which showsa heart valve having a plurality of nested circular elements. However,in view of the extremely specialized and highly delicate nature of theuse to which a heart valve is put, there is a continuing need for newand improved valve structures therefor.

Heart valves generally include a substantially fixed outer support partto which a suitable fabric such as a Dacron or Teflon fabric isattached, this fabric serving as the means for connecting the heartvalve to the walls of the passageway. However, while these support partshave generally been fixed elements, the systems in which they are usedare dynamic parts, i.e., passages in the heart which expand and contracteach time that the heart beats. Also, the heart shrinks in sizefollowing reparative surgery. This conflict between the dynamic natureof the cardiovascular system and the static nature of the conventionalheart valve support means creates problems, the solutions to which thepresent invention is directed.

SUMMARY OF THE INVENTION Thus, it is a purpose of this invention toprovide a new and improved prosthetic structure for the cardiovascularsystem which improves upon and solves problems associated withstructures known heretofore.

The present invention provides a new and improved means for retaining aheart valve of the construction in the passageway of a cardiovascularsystem. According to the invention, the connecting means is an annulararrangement surrounding the heart valve and so connected to the heartvalve that it is permitted to expand and contract radially while at thesame time it is capable of being positively secured to the walls of thepassageway. A cloth is connected to the outer periphery of the annulararrangement and the cloth is sutured to the walls of the passageway.

Within this basic structure, the annular arrangement can have manydifferent forms. The heart valve will preferably have formed on theouter circumference thereof an outwardly extending circumferentialflange to which the annular arrangement would be attached for slidingmovement both circumferentially therealong and radially relativethereto. In a preferred embodiment, the annular arrangement willcomprise a plurality of arcuate segments, each having a slot on itsinner periphery to engage said flange. Of course a circumferential spacewill be provided between adjacent segments permitting them to moveradially relative to the heart valve. The segments may be interconnectedcircumferentially by means which permit relative circumferential slidingmovement or the circumferential engagement of the segments may simply beprovided by the cloth fabric referred to above which will extend in acontinuous circle all about the outer periphery of the annulararrangement. The cloth should have a degree of elasticity so that itcould stretch and relax circumferentially as the segments moved radiallyoutwardly and inwardly respectively.

In another embodiment, the annular arrangement may take the form of asingle loop which overlaps itself and is thus capable of increasing anddecreasing the extent of overlap so as to expand and contract radiallyrelative to the heart valve.

With the above described heart valve retaining means, it is now possibleto secure the heart valve in place during the operative procedure, afterwhich the overall dimensions of the heart valve (i.e., the heart valveand its retaining means) will shrink in size concurrently as the heartshrinks in size following surgery. This has the advantage of minimizingpressure on the conduction system on the heart and thus reducing thepossibility of subsequent arrhythmias. In addition, this will minimizethe possibility of the sutures tearing out by the gradual shrinkage ofthe heart, which might be the case if the overall heart valve structurewere completely fixed relative to the dynamic, shrinking heart. Further,the normal action of the heart includes expansion and contraction and byallowing motion of the valve during this normal cardiac cycle, thepossibility is reduced of the sutures tearing out until such time as thevalve is anchored to the passage walls by the ingrowth of fibroustissues.

While the heart valve retaining means is usable with essentially anytype of heart valve, the present invention also provides a new andimproved heart valve structure capable of being used in combination withthe new and improved annular retaining means or separately therefrom.

According to the preferred embodiment, this new heart valve structurecomprises a plurality of circular and ring shaped segments which, in theclosed condition interfit with each other in a single plane, and whichin an expanded condition separate from each other axially to an extentpermitted by retaining struts to permit fluid to low therethrough. Thisstructure provides several advantages. First, in the closed conditionthe valve is rather compact since all'elements lie in a single plane.Secondly, the structure is such that a good seal may be formed betweenthe individual. elements of the valve in the closed condition. Further,in the open condition the elements can separate from each other arelatively large distance, thus permitting free flow of fluidtherethrough. Moreover, the valve structure provides a uniquecombination of ruggedness and flexibility. This is so because theindividual valve elements are plates which can be formed of a strongmetal material containing the retaining struts to interconnect them inthe open condition, and the various ring elements can turn out of theirnormal transverse planes, thus permitting a certain degree offlexibility. In a preferred arrangeand improved prosthetic device forthe cardiovascular system.

It is another object of this invention to provide a new and improvedheart valve retaining means which is capable of undergoing radialexpansion and contraction.

It is still another object of this invention to prov de a new andimproved valve retaining means having a plurality of arcuate segmentsarranged annularly around the valve for connecting the valve to thepassageway in the cardiovascular system, the annular arrangement beingmovable radially.

It is another object of this invention to provide a new and improvedheart valve having a plurality of circular or ring shaped elementswhich, in the closed position, lie in a common plane, and which in theopen position, separate axially from each other to an extent permittedby struts.

It is still another object of this invention to provide a new andimproved heart valve having a plurality of circular or ring shapedelements movable between an open position. and a closed position incombination with a radially adjustable annulus for connecting the heartvalve to the passageway of the cardiovascular system.

Other objects and the advantages of the invention will become apparentfrom the detailed description to follow together with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS There follows a detailed description.of preferred embodiments which are to be read together with theaccompanying drawings.

FIG. 1 is a plan view of a heart valve constructed in accordance withthe present invention in combination with an adjustable annularretaining means therefor.

FIG. 2 is a cross-sectional view taken along line 22 of FIG. 1.

FIG. 3 is a cross-sectional view similar to FIG. 2 but showing the valveelements in the valve-opened condition and excluding the adjustableannular retaining structure.

FIG. 4 is an enlarged, long line 44 of FIG. 2.

FIG. 5 is a cross-sectional view similar to the righthand side of FIG. 2but showing a modification of the invention.

FIG. 6 is a plan view showing a portion of a modified annular valveretaining means.

FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. 6.

FIG. 8 is a perspective view of an elementof FIGS. 6 and 7.

FIG. 9 is a plan view similar to FIG. 1 but omitting the valve itselfand showing a modified structure of the annular valve retaining means.

FIG. 10 is a perspective view of an element of FIG.

partial sectional view taken FIG. 11 is a plan view similar to FIG. 1but omitting the valve structure and showing a modification of theannular valve retaining means.

FIG. 12 is a cross-sectional view taken along line 12-12 of FIG. 11.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings,like elements are represented by like numerals throughout the severalviews.

FIGS. 14 show a heart valve assembly 10 having a heart valve 11 incombination with an expandable annular retaining means 12.

Referring in particular to FIGS; 2 and 3, the heart valve 11 comprisesacylindrical outer ring 13, intermediate annular rings 14 and 15, and aninner circular element 16. Each of elements l4, l5 and 16 have abevelled frusto-conical outwardly facing surface 17 and each of elements13, 14 and 15 have inwardly facing frustro-conical surfaces 18. As isapparent in FIG. 2, in the closed condition of the valve, facingsurfaces 17 and 18 engage each other to seal the passageway in which thevalve is located. Each one of the elements 13, 14 and 15 includes alower annular shoulder 19. In turn, each of the elements 14, 15 and 16has fixed thereto a plurality of struts 20, 22, and 23, respectively,which struts extend downwardly from the element with which it isconnected and then outwardly as shown at 21 for the righthand element 20in FIGS. 2 and 3 to engage the shoulder 19 of the element immediately beneath it. In this manner, the struts limit the upward and hence theopening movement of the valve.

In practice, the valve must of course assume any orientation and ofcourse it does not depend on gravity to open and close. In practice,pressure on the upstream side of the valve (the lower part in FIGS. 2and 3) would open the valve, and then a pressure differential in theopposite direction during another part of the car diac cycle wouldclosethe valve.

In FIG. 2, the walls of the passageway in which the valve is located isdesignated by 25. In FIG. 2, the flow would be in the upward direction.Referring now to FIGS. 1, 2 and 4, the valve is secured in thepassageway 25 by the adjustable annular retaining means in the followingmanner. A flange 30 projects outwardly from the outer ring 13 andextends continuously around the valve and includes an upwardly extendinglip 31. In this embodiment, the annular retaining means comprises aplurality of arcuate segments 32, each of which includes an inner cavity33 for receiving the lip 31 of the flange 30 in such a manner that thesegment 32 can move radially relative to the flange 30. The segment 32also includes an outer element 34, the purpose of which is to secure tothe segment 32 a clock 35 of fabric or the like. As shown in FIG. 1,this cloth 35 will extend circumferentially completely around theannular retaining means 13, even across the spaces between adjacentsegments. The annular retaining means 12 is then connected to wall 25 bymeans of sutures secured to the fabric 35 in a manner known per se, andit also extends from wall 25 radially inwardly to completely cover themeans 12. It is connected above to the outside of ring 13 and below tothe radial inner side of bottom wall 39.

The segments 32 are probably adequately supported in all directions bytheir engagement with the flange 30 and lip 31. However, to furtherguide these elements 32 in their relative movement, guiding means 36-38may be provided. This guiding means includes an elongated hollow slot 36attached to each segment 32, each slot 36 having fixed thereto a rod 37extending into the slot 36 of the adjacent segment and including at itsend a head 38 engageable in said adjacent slot 36. See FIG. 4.

Means must be provided for preventing fluid flow through the expandableannular retaining means when the valve is in the closed position, i.e.,around the flange 30 or between the segments 32. For this purpose, asuitable flexible waterproof material can be connected to the two facingends of adjacent segments 32 and also from the lower end of element 13across to the bottom wall 39 of the segment 32 as shown at 43 in FIG. 2.In lieu of element 43, the flange 30 can of course engage the bottomwall 39 in a tight watertight manner.

FIG. 5 shows a modification of the invention wherein the flange 30 isreplaced by a spring loaded flange 40 which has a lower portion springbiassed downwardly against bottom wall 39 at point 41. This provides ascraping action of the bottom wall 39 and prevents thrombus formation ofthe components until final closure is established. In addition, this canof course provide the fluid tight seal preventing fluid to flow throughthe annular retaining means 12 when the valve is in-the closed position.

FIGS. 6-8 show another modification of the annular retaining means 12.In this case, only the outer ring 13 of the valve 11 is shown and theflange 30 is replaced by a simple flange 45 which does not have a lip31. In this embodiment, each of the arcuate segments 46 include a rod 47integral therewith and projecting circumferentially therefrom and havingat its outer end an enlarged head 48. On its opposite circumferentialside, the segment 46 includes an opening 49 large enough to receive rod47, but not large enough to receive head 48. On its radial inner side,the segment 46 includes a slot 50 adapted to receive the flange 45. Inthe same manner as in the embodiment of FIGS. 1-5, a fabric materialsuch as Dacron or Teflon surrounds and is attached to the outerperiphery of the segments 46 for attaching the valve means to the wellsof passageway 25.

The embodiment of FIGS. 9-10 is similar to the embodiment of FIGS. 6-8except that the shape of the individual segments is somewhat changed. Inthis case, the arcuate segments 55 are cylindrical and include at oneend a circular arcuate rod 56 which does not have an enlarged head butwhich is adapted to fit through the opening 57 on the adjacent arcuatesegment. Slot 58 is provided on the radial inner facing surface toengage flange 45, and a fabric ring surrounds the outer periphery of thesegments 55.

In the embodiment of FIGS. 11 and 12, a single element 65 extendscompletely around the valve means and overlaps itself loosely through aharness 67 which permits the element 65 to decrease and increase itsoverlap, thus expanding and contracting, radially, respectively. Aplurality of inwardly facing slots 66 engage flange 45 and a fabric ring68 completely surrounds the element 65 for attaching the same to thewalls of passage 25.

In all of the embodiments, it will therefore be seen that the expandableannular retaining means 12 is capable of limited radial expansion andcontraction relative to the valve member itself. Thus, in operation thevalve with an adjustable annular retaining means can be inserted into apassage in the cardiovascular system during which time the passage willbe enlarged. Then, following surgery, as the passage shrinks, theannular retaining means will also contract, moving inwardly as theindividual segments move closer together. For example, in the embodimentof FIGS. 1 and 2, the means 12 is shown in its radial outer position.Note the space A between the lip 31 and the outer side of cavity 33 anda similar space B between the inner wall of cavity 33 and the element13. Also not in FIG. 1 that the segments 32 are spaced apart from eachother circumferentially. The assembly might be installed in thepassageway 25 in this manner. Then, in the course of time, thepassageway 25 would shrink and the means 12 would move radiallyinwardly, the cavities 33 moving in on the flange 30 as the spaces A andB reduce in size. Thus, contrary to the prior art wherein such shrinkagewould cause a stress where the wall engaged the support, in this casethe wall can simply shrink, moving with it the valve retaining means.The valve retaining means would be so dimensioned that even aftershrinkage had been completed, the spaces A and B would not be completelyeliminated, i.e., the element 13 would not touch the element 33. Thiswould leave some leeway for the means 12 to expand and contract as thepassageway 25 expanded and contracted during the normal cardiac cyclewithout tearing the valve from its sutures anchoring the fabric 35 tothe walls of passageway 25.

In the preferred embodiment of the valve 11, the structural elements 13,14, 15 and 16 would be made entirely of steel containing struts. In anormal useage of the present invention, a total change in diameter ofapproximately three to four millimeters would be sufficient forpreventing the sutures from being torn.

Although the invention has been described in considerable detail withrespect to preferred embodiments thereof, it will be apparent that theinvention is capable of numerous modifications and variations apparentto those skilled in the art without departing from the spirit and scopeof the invention.

I claim:

1. In combination, a valve means and a valve retaining means forsecuring the valve means to the internal walls of a passageway in acardiovascular system as a prosthetic replacement in the cardiovascularsystem, said valve means being movable between open and closed positionsand including fixed external means at the outer periphery thereof; saidretainer means including an annular arrangement surrounding the valvemeans and including at least one stiff element operatively engaging theexternal means of the valve means, at least one of said external meansand stiff element having slot means therein slidably engaging the otherfor radial movement relative thereto, the retainer means thus beingexpandable and contractable relative to the valve means transversely ofthe direction of fluid flow in the passageway as the passageway enlargesand contracts.

2. The invention according to claim 1, said retainer means comprising-asingle element surrounding the valve means and overlapping itselfcircumferentially.

3. The invention according to claim 2, said single element including atleast one slot on the radial inner side thereof and a radially outwardlyextending circumferential flange on the outer wall of the valve meansengaging said at least one slot so as to permit sliding radial movementof the single element relative to the flange.

6. The invention according to claim 5, wherein said flange'includes aspring means for urging said flange into engagement with the walls ofthe slots.

7. The invention according to claim 1, including a ring of fabricmaterial surrounding the annular arrangement and adapted to be connectedto the said passageway in the cardiovascular system.

8. The invention according to claim 1, said retaining means including aplurality of arcuately extending segments engaging the valve means forsaid radial sliding movement relative thereto.

9. The invention according to claim 8, said segments including a radialinner cavity having a radially inwardly opening slot slidingly engaginga circumferential flange on the valve means and an outer part adapted tosecure thereto a fabric ring.

10. The invention according to claim 8, said segments being slidinglyconnected to each other circumferentially such that they can movecircumferentially relative to each other as well as radially relative tothe valve means.

1 l. The invention according to claim 8, each segment having an openingat one circumferential end thereof and a rod extending from the othercircumferential end thereof, the rods slidingly interfitting intoopenings in the respective adjacent segment.

12. The invention according to claim 11, the segments, viewed in aradial plane, being essentially circular.

13. The invention accordng to, claim 11, the segments, viewed in aradial plane, being essentially rectangular.

14. A valve adapted to be used as a replacement for a valve in acardiovascular system comprising a valve body including a plurality ofconcentric ring shaped elements having inner and outer bevelled outersurface and a ring shaped outer ring element having a bevelled innersurface, said circular inner element, said ring shaped elements and saidring shaped outer element interfitting to lie in a common plane when thevalve is closed, struts on each of said ring shaped elements and saidinner circular element having bent outer ends to engage the adjacentelement to limit the separation of said elements when the valve isopened, and a radially expandable contractable annular retainer meanscomprising at least one stiff segment arranged in an annulus around thevalve body and having an inner cavity formed thereon with a radiallyinwardly facing slot in said cavity and a stiff flange means on saidring shaped outer element slidably engaging in said slot.

15. A valve accordng to claim 14, wherein said flange means includesspring means for urging said means into engagement with the walls of theslots.

16. A valve according to claim 14, including a plurality of saidsegments arranged annularly about the valve. l l

1. In combination, a valve means and a valve retaining means forsecuring the valve means to the internal walls of a passageway in acardiovascular system as a prosthetic replacement in the cardiovascularsystem, said valve means being movable between open and closed positionsand including fixed external means at the outer periphery thereof; saidretainer means including an annular arrangement surrounding the valvemeans and including at least one stiff element operatively engaging theexternal means of the valve means, at least one of said external meansand stiff element having slot means therein sLidably engaging the otherfor radial movement relative thereto, the retainer means thus beingexpandable and contractable relative to the valve means transversely ofthe direction of fluid flow in the passageway as the passageway enlargesand contracts.
 2. The invention according to claim 1, said retainermeans comprising a single element surrounding the valve means andoverlapping itself circumferentially.
 3. The invention according toclaim 2, said single element including at least one slot on the radialinner side thereof and a radially outwardly extending circumferentialflange on the outer wall of the valve means engaging said at least oneslot so as to permit sliding radial movement of the single elementrelative to the flange.
 4. The invention according to claim 1, whereinsaid valve means includes an outwardly extending circumferential flangeengaging within slot means in said retainer means to operativelyinterconnect said valve means and said retainer means.
 5. The inventionaccording to claim 4, said retainer means comprising a plurality ofindividual segments arranged in an annulus around said valve body, eachsegment having an inner cavity formed thereon with a radially inwardlyfacing slot in said cavity engaging said flange of the valve means. 6.The invention according to claim 5, wherein said flange includes aspring means for urging said flange into engagement with the walls ofthe slots.
 7. The invention according to claim 1, including a ring offabric material surrounding the annular arrangement and adapted to beconnected to the said passageway in the cardiovascular system.
 8. Theinvention according to claim 1, said retaining means including aplurality of arcuately extending segments engaging the valve means forsaid radial sliding movement relative thereto.
 9. The inventionaccording to claim 8, said segments including a radial inner cavityhaving a radially inwardly opening slot slidingly engaging acircumferential flange on the valve means and an outer part adapted tosecure thereto a fabric ring.
 10. The invention according to claim 8,said segments being slidingly connected to each other circumferentiallysuch that they can move circumferentially relative to each other as wellas radially relative to the valve means.
 11. The invention according toclaim 8, each segment having an opening at one circumferential endthereof and a rod extending from the other circumferential end thereof,the rods slidingly interfitting into openings in the respective adjacentsegment.
 12. The invention according to claim 11, the segments, viewedin a radial plane, being essentially circular.
 13. The inventionaccordng to claim 11, the segments, viewed in a radial plane, beingessentially rectangular.
 14. A valve adapted to be used as a replacementfor a valve in a cardiovascular system comprising a valve body includinga plurality of concentric ring shaped elements having inner and outerbevelled outer surface and a ring shaped outer ring element having abevelled inner surface, said circular inner element, said ring shapedelements and said ring shaped outer element interfitting to lie in acommon plane when the valve is closed, struts on each of said ringshaped elements and said inner circular element having bent outer endsto engage the adjacent element to limit the separation of said elementswhen the valve is opened, and a radially expandable contractable annularretainer means comprising at least one stiff segment arranged in anannulus around the valve body and having an inner cavity formed thereonwith a radially inwardly facing slot in said cavity and a stiff flangemeans on said ring shaped outer element slidably engaging in said slot.15. A valve accordng to claim 14, wherein said flange means includesspring means for urging said means into engagement with the walls of theslots.
 16. A valve according to claim 14, including a plurality of saidsegments arranged annularly about the valve.